1. Field of the Invention
The present invention relates to a disk storage device for storing recording data on a disk using an optical beam emitted from an optical head. Particularly, the present invention relates to a disk storage device that can correct and record the luminous output of an optical head according to variations in recording sensitivity of a disk.
2. Description of Related Art
CD-R (Compact Disk-Recordable) drives or CD-RW (Compact Disk-ReWritable) drives of the CD (Compact Disk) family are well known disk storage systems for recording digital data onto a disk using an optical beam emitted from an optical head.
Disks onto which data is recorded by the recording devices associated with such disk storage systems have different recording sensitivities due to different material qualities used by manufacturers, or due to variations between materials use or quality within a single disk.
In disk storage devices, the luminous output of an optical head at the recording time is set to an optimum recording level for recording data onto a disk.
For that reason, in the disk storage devices, the luminous output of an optical head at the time of recording is set to an optical recording level to compensate for recording sensitivity differences of a disk.
The optimum recording level of a luminous output emitted from an optical head at the time of recording is set by stepwise varying the luminous output to execute trial writing in an calibration area for luminous output setting. The calibration area is disposed differently from the program area for actually recording data onto a disk.
While data is being recorded onto a disk during trial writing using the luminous output preset as an optimum record level, the reflection level of a record pulse is detected. The luminous output is then corrected according to the reflection level to adjust the luminous output to an actual data recording state to a practical record level.
However, since the formation status of data recorded onto a disk is not actually detected, the luminous output of an optical head is not set to an actual optimum recording level. Although the disk storage device is designed to speed up the recording rate, associated with the speeding up of the recording rate of the disk storage device is s narrowing of the pulse width of a record pulse. Hence, it is difficult to detect the reflective level of a recording pulse. It is not now possible to correct and adjust the luminous level to an optimum recording level in an actual data recording state during disk recording.
This invention is made to overcome the above-described problem. It is an object of the present invention to provide a disk storage device that can correct and record the luminous output of an optical head according to variations in recording sensitivity of a disk.
According to the present invention, the record-start-position detection unit detects a record-start-position where writing of additional data to be recorded onto the disk begins. Meanwhile, the synchronous setting unit creates recording data to be additionally synchronously written with the recorded data. New recording data is additionally written continuously to data recorded on a disk. The additional writing is started in synchronous with recorded data. The optical head reads data recorded onto a disk immediately before a halt of recording every time the record decision unit judges a halt of recording. The record-state detection unit detects the formation status of the recorded data. The head output control unit sets the luminous output of the optical head at the beginning of additional writing according to the recording state judged by the record-state detection unit. Thus, an optimum recording level is set by actually detecting the formation of data recorded on a disk every additional writing operation and by stepwise correcting the luminous output of the optical head.